Parallel jaw pliers

ABSTRACT

The parallel jaw pliers of this invention are primarily for use in dentistry and particularly in orthodontics. The pliers provide a compact structure permitting the jaws to be moved in a parallel manner while occupying a minimum space such as in the mouth of a patient. The pliers consist of only four major members retained by a transverse pin which maintains the members in sliding alignment while acting as a pivot for only the handles. The jaws are carried between the handle members and on and by actuating pins extending from the handle members. As the pins are moved they maintain the jaws in a parallel arrangement as the handle members are moved.

United States Patent 1 Cusato [54] PARALLEL J AW PLIERS [73] Assignee:Henry Mann, Inc., Feasterville, Pa.

[22] Filed: July 2 2, I971 [2i] Appl. No.: 165,022

[ 51 Jan. 16, 1973 Primary Examiner-Robert C. Riordon AssistantExaminer-Roscoe V. Parker Attorney-Ralph R. Roberts [5 7 ABSTRACT Theparallel jaw pliers of this invention are primarily for use in dentistryand particularly in orthodontics. The pliers provide a compact structurepermitting the jaws to be moved in a parallel manner while occupying aminimum space such as in the mouth of a patient. The pliers consist ofonly four major members retained by a transverse pin which maintains themembers in sliding alignment while acting as a pivot for only thehandles. The jaws are carried between the handle members and on and byactuating pins extending from the handle members. As the pins are movedthey maintain the jaws in a parallel arrangement as the handle membersare moved.

11 Claims, 5 Drawing Figures PATENTEDJAH 16 1975 3.710.657

sum 1 OF 2 INVENTOR. ANTHONY J. CUSATO AGENT PATENTEDJAH 16 I975 SHEET 2[IF 2 INVENTOR. ANTHONY J. CUSATO BACKGROUND OF THE INVENTION 1. Fieldof the Invention With reference to the classification of art asestablished in the United States Patent Office the present inventionpertains to the general class of Metal Working and more particularly tothe subclass of plier type" assembling and disassembling apparatus.

2. Description of the Prior Art Pliers whose gripping jaws are adaptedto remain parallel or substantially parallel during their opening andclosing actuation are well known. Such pliers are represented inseveralU.S. patents among which is particularly noted U.S. Pat. No.427,220 to BERNARD which issued May 6, 1890. Also noted are U.S. Pat.No. 168,924 to RUSSELL as issued Oct. 19, 1875; U.S. Pat. No. 188,262also to RUSSELL as issued'on Mar. 13, 1877; U.S. Pat. No. 188,408 toQUIRK as issued on Mar. 13, 1877; U.S. Pat. No. 491,231 to VONAl-IAUS etal., on Feb. 7, l893-and U.S. Pat. No. 1,274,187 to NELSON as issued onJuly 30, 1918.

Pliers similar to those shown in the BERNI-IARD patent have been knownfor many years in the field of dentistry. However, those parallel jawpliers that have been known and used in particular in the field ofdentistry and orthodontics have been, because of their design, of a sizewhich is larger than desirable. The number of pieces necessary toprovide the parallelogram movement of the BERNI-IARD and like typepliers results in a pliers having a bulky jaw construction whereas inthe restricted area of children's mouths the pliers should be as smallaspossible. In the present invention it is contemplated that a smallparallel jaw pliers be provided for use in orthodontics in which theyare only four moving members and in which the central retaining pin actsonly as a means for pivotally retaining the handles while retaining thefour members in a determined sliding relationship.

SUMMARY OF THE INVENTION The presentinvention may be summarized at leastin part with reference to its objects.

It is an object of this invention to provide, and it does provide, aparallel jaw pliers for use in orthodontics wherein a small and compactsize is achieved by limiting the major components tofour moving membersand retaining these members by a transverse pin which is a pivot pin foronly the handle members.

It is a further object of this invention to provide, and

it does provide, a parallel jaw pliers for use in orthodontics wherein asmall and compact size is achieved by making like handle and jaw memberswhich are retained'in a pivoted and sliding relationship by a transversepin which does notprovide a pivotal relationship with the jaw members.The parallel actuation of the parallel positioned jaws is provided bypins carried by the handle members so as to actuate only one end of eachcooperativejaw member.

The parallel jaw pliers of this invention preferably comprises two likejaw members which are arranged at one hundred eighty degrees to eachother. The forward or outer portion of each of the jaws is provided witha pivot pin hole while therear portion has a slot disposed to receive aguide pin. A pair of like handle members is also arranged at one hundredeighty degrees to each other and on side plate portions carry pivotpins. The front pin is disposed to pivotally seat in the pin hole in theadjacent jaw while the rear pin passes by a cutout in the near jawmember to enter the slot in the other jaw member. A retaining pivot pinaligns and pivotally retains the handles in a determined rotaryalignment as it, the pin, passes through a clearance hole or slotprovided in each of the jaw members.

In addition to the above summary of the following disclosure is detailedto insure adequacy and aid in understanding of the invention. Thisdisclosure, however, is not intended to prejudice that purpose of apatent which is to cover each new inventive concept therein no matterhow it may later be disguised in form or additions of furtherimprovements. For this reason there has been chosen a specificembodiment of the parallel jaw pliers as adopted for use in the field oforthodontics and showing a preferred means for manufacture and assembly.This specific embodiment and an alternate handle spacing means have beenchosen for the purposes of illustration and description as shown in theaccompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. lrepresents a side or plan viewof the parallel jaw pliers of this invention, the pliers shown beingsubstantially full scale and with the jaws in a closed condition;

FIG. 2 represents an edge view of the pliers of FIG. 1, the view takenon the line 2-2 and looking in the direction of the arrows;

FIG. 3 represents the plan view of the pliers of FIG. 1 but with thejaws in about the fully opened condition,

and in phantom outline showing the jaws and handles in an intermediatelyopen condition;

FIG. 4 represents an isometric exploded view show ing the relationshipof the four main members of the pliers to each other and to the pinmembers carried by the handles, the pins adapted to provide the supportand the planar actuation of the jaws, and

FIG. -5 represents an isometric view of a pivot pin and a bushing foruse in an alternate pliers assembly.

The names, however, are intended to be generic in their application.Corresponding reference characters refer to like members throughout theseveral figures of the drawing.

The drawings accompanying and forming part of this specificationdisclose certain details of construction for the purpose of explanationof the broader aspects of the invention, but it should be understoodthat structural details may be modified in various respects withoutdeparture from the concept and principles of the invention and that theinvention may be incorporated in other structural forms than shown.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in particular tothe assembled pliers as seen in FIGS. 1, 2 and Sand the disassembledplier components as seen in FIG. 4, the pliers include an upper handleportion 10 and a like lower handle portion 12. These handles arecontemplated as being substantially identical with one turned one fromthe other. Handle 10 is pivotally connected to handle 12 by means of apivot pin 13 extending through boss 14 and pivot aperture 15 formed inboth handles and 12. Upper and lower jaws 16 and 18 are also anticipatedas being identical components turned 180 from each other.

Referring now particularly to the handle portion 10 as seen in FIG. 4said handle is provided with an outer wall portion 20 in which there isfastened or molded so as to extend inwardly therefrom two pivot pinsidentified as 22 and 23. The front or forward pin 22 extends inwardlyonly a short distance while the rear pin 23 extends a further distanceinwardly to be hereinafter more fully defined. Handle 12 also has anouter wall portion 30 like the portion 20 of handle 10. Extendinginwardly from wall 30 and as seen in dashed outline are pins 32 and 33.The forward pin 32 extends inwardly a very short distance from the wallwhile the pin 33 extends inwardly a longer distance, which distances arecomparable to those also provided by the pins 22 and 23 as they extendfrom the wall 20 of handle 10.

Referring now to the jaw members 16 and 18 it is to be noted that thejaw face portions 35 and 36 are disposed to be parallel to each otherand to remain parallel when the jaw members are moved toward each other.Extending rearwardly from the heavier face portions of the jaws 16 and18 are like wall or plate portions 40 and 41. Holes 43 and 44 are formedin these plate portions with each hole or aperture sized so as to be asnug rotary fit with the mating pin. Pin 22 is rotatably mounted in hole43 in plate 40 while the pin 32 is rotatably mounted in hole 44 formedin plate 41. In the back or rear portions of the plate portions 40 and41 are slots 46 and 47 disposed to slidably receive and engagerespectively the pins 23 and 33. Pin 23 enters and engages slot 47 injaw 18 while pin 33 enters and engages slot 46 in jaw 16. In both plateportions 40 and 41 and intermediate the front hole and the rear slot isformed an elongated hole with hole 49 being provided in plate 40 andhole 50 being provided in plate 41. In each plate the elongated hole isdisposed to permit the free passage of pin 13 therethrough. Althoughshown as an elongated hole 49 in plate portion 40 and as an elongatedhole 50 in plate portion 41 these clearance means may be larger drilledholes or slots just so that they provide a clearance for pin 13 afterthe assembly of the pliers and during the operation of the pliers.

In an assembled condition the short pin 22 extending from wall 20 entershole 43 to act as a pivot support for the front portion of jaw 16 whilepin 23 passes over the contoured rear portion 52 of jaw 16 to enter andengage slot 47 in jaw 18. Pin 32 carried by wall 30 enters hole 44 injaw 18 and does not extend beyond the inner or left face of the plateportion 41. The rear and longer pin 33 passes by the contoured relief 54in jaw 18 to enter and engage slot 46 in plate portion 40 but does notextend beyond the outer or left face of the plate portion 40. In anassembled condition the outer wall face-to-face relationship to providea determined spacing between the inner faces of walls 20 and 30.

ASSEMBLY AND OPERATION OF THE PARALLEL JAW PLIERS 1n the assembledcondition of FIGS. 1, 2 and 3 the parallel jaw pliers of this inventioncontemplate that the thickness of the outer wall portion 20; jaw plateor wall portion 40; jaw plate or wall portion 41 and outer wall portion30 are substantially the same thickness. Pin 22 extends from the innerface of outer wall 20 an amount at least slightly less than thethickness of jaw plate portion 40. In like manner pin 32 extendsinwardly from the inner face of outer wall 30 an amount at leastslightly less than the thickness of jaw plate portion 41.

Pin 23 extends from the inner face of outer wall 20 an amount which isat least a slight amount less than the combined thickness of jaw plateportions 40 and 41. Pin 33 is like pin 23 in that said pin 33 extendsfrom the inner face of outer wall 30 an amount which is at least aslight amount less than the combined thickness of jaw plate portions 41and 40.

As assembled, pin 23 extends through the contoured rear relief portion52 of jaw 16 to enter and extend nearly through slot 47 in jaw 18. Inlike manner pin 33 extends through contoured rear relief portion 54 ofjaw 18 to enter and extend nearly through slot 46 in jaw 16. Pivot pin13 is fixedly mounted in the aperture 15 in the outer wall portion 20and passes through elongated holes 49 and 50 and into pivot aperture 15in the outer wall portion 30 where the end of the pin is preferablyriveted to provide a retaining head while the retained handle 12 isrotatable therearound. Pin 13 axially aligns handle 12 and the grippinglength of the pin is made of a calculated length to provide a determinedsnugness of the sliding joint. Bosses 13 are of a determined length toprovide a desired degree of play for the movement of plate portions 40and 41.

As seen in FIG. 2 the jaws 16 and 18 are tapered from the wall sectionto the outer end whereat the jaws may be about five thirty-seconds of aninch in width and the combined thickness at the same tip end may also beabout five thirty-seconds of an inch.

As the handles 10 and 12 are rotated around pin 13 the pin 22 carried byhandle 10 supports and moves the forward portion of jaw 16 while pin 23extends into slot 47 of jaw 18 to support and move the rear portion ofjaw 18. Pin 32, carried by handle 12, supports and moves the forwardportion of jaw 18 while pin 33 extends into slot 46 to support and movethe rear portion of jaw 16. Pin 13 passes through bosses 14 in thehandles, said bosses being freely movable in the elongated holes 49 and50 so as to not engage or provide any support ofjaws 16 and 18 or forthe retaining of the jaws in a parallel condition. Pins 22 and 32 inaddition to moving the jaws l6 and 18 also retain these jaws in adetermined relationship to handles 10 and 12. The rear pins 23 and 33 inthis invention are disposed to only swing the jaws and to support andmaintain their parallel condition. The slots in which these pins rideare not extensive and the travel of the pin in the slot in the pliers asreduced to practice is less than one-eighth of an inch.

As reduced to practice, the pliers of this invention have handle made asan investment casting of stainless steel with bosses 14, apertures andpins 22 and 23 cast integral therewith. Handle 12 is also a castingidentical to handle 10 with boss 14 and aperture 15 provided in handle12 as isprovided in handle l0. Jaw 16 is also a precision investmentcasting of stainless steel and when turnedl80becomes the exemplified jaw18. The normal finishing by polishing which is conventional in plierswhich must be sterilized is of-cours'e contemplated in the presentpliers. By making pins 22 and 23 on handle 10 and the likepins 32 and 33on handle 12 of a cantilever design permits the pliers to be reduced inbulk and members and the few moving parts are easy to form and assemble.p

It is of course to be noted that the forward pins 22 and 32 engage theadjacent jaw portions so that the load on them is essentially in shearwhile the longer rear pins are subjected to both bending and shear. Ifdesired, the pins can be reversed as to the jaw members actuated. Thepin apertures and slots as far as the jaw configuration can be reversedif desired, as only one pin hole and one slot are required in each jawplate portion. It is also preferred that pins 22 and 23 as well as 32and 33 be like distances from the axis of pin 13 and when the jaws arein a parallel condition the pins are a like distance above and below theplane of the jaw face.

Other pin arrangements are possible but to reduce assembly problems itis preferable to make handles 10 and 12 and the jaws 16 and 18 exactlylike the other which requires that the pin combinations of 22 and 23 aremirror arrangements to that of pins 32 and 33. It is also to be notedthat the pins 22, 23, 32 and 33 may be mounted in the jaw plate portionswhile the pivot hole and slot would then be formed in the face of theend of the outer wall portions of the handle members.

ALTERNATE SPACER OF FIG. 5

Referring finally to FIG. 5 it is to be noted that handles l0 and 12instead of having the bosses 14 formed thereon as in FIG. 5 may havethese bosses omitted. In this condition it is assumed that the innerfaces of the outer wall portions and will be of a planar configuration.A determined assembled spacing between these walls is then provided by aspacer 60 of a length which may be a couple of thousandths of an inchmore than the combined thickness of the rear plate portions and 41. Bore61 is preferably made as a sliding fit on the shank of pin 13. Theassembly of the handles, jaws with spacer 60 is substantially like thatin FIGS. 1, 2 and 3 above-described. I

Terms such as left, right, up," down, bot tom," top, front, back," in,out," clockwise, counterclockwise" and the like are applicable to theembodiment shown and described in conjunction with the drawings. Theseterms are merely for the purposes of description and do not necessarilyapply to the position in which the parallel jaw pliers may beconstructed or used.

While a particular embodiment of the parallel jaw pliers have been shownand described it is to be understood the invention is not limitedthereto since modifications may be made within the scope of theaccompanying claims and protection is sought to the broadest extent theprior art allows.

What is claimed is:

1. A pliers assembly in which the jaws are carried and are movable sothat the gripping faces on the jaws are substantially parallel throughtheir limits of movement, said pliers including: (a) a pair of handlemembers adapted for grasping by the user, each of said handle membershaving an outer wall portion; (b) a pivot pin adapted to retain thehandle members in a pivotal relationship to each other and disposed toretain said outer wall portions with a determined distance therebetween;(c) a pair of jaw members each having a gripping face portion, said jawmembers arranged so that the face portions are substantially paralleland disposed to be contiguous when brought together, each jaw memberhaving a rear plate portion and with each plate portion having aclearance means therethrough, said clearance means disposed toaccommodate the presence of the pivot pin when the plate portions of thejaw members are slidably retained between the outer wall portions of thehandle member; (d) a fixed short pin carried on the outer wall portionof each handle and a mating pinreceiving aperture formed in a contiguousportion of the rear plate portion of each jaw member and disposed toreceive and pivotally support said short pin, the pin and aperture beingdisposed a determined distance from the pivot pin; (e) a fixed longerpin carried on the outer wall portion of each handle and a mating pinreceiving slot formed in a portion of the rear plate portion of each jawmember, the longer pins and slots being disposed a determined distancefrom the pivot pin on the side opposite the short pin, relief meansformed in the rear plate portion of each jaw member whereby said longerpin of each handle may pass the rear plate portion of the jaw membercontiguous therewith to respectively engage said slot in the rear plateportion of the other of said jaw members, and (f) means for mounting andretaining the short and longer pins in a cantilever manner as the pliersare assembled and used.

2. A pliers assembly as in claim 1 in which the short pin is carriedforwardly of the pivot pin and the longer pin is carried rearwardly ofthe pivot pin.

3. A pliers assembly as in claim 2 in which the outer I wall portions ofthe handle members and the plate portions of the jaw members are ofsubstantially the same thickness with each of the short pins being atleast slightly less in length than the thickness of a rear plate portionof a jaw member and with the longer pin of a length substantially longerthan the thickness of a rear plate portion of a jaw member and of alength of at least slightly less than the combined thicknesses of thetwo adjacent rear plate portions of the two jaw members.

4. A pliers assembly as in claim 3 in which the axis of the short andlong pin on one outer wall portion lays in a plane common with the axisof the pivot pin.

5. A pliers assembly as in claim 4 in which the short and long pins aredisposed an equal distance from the pivot pin.

6. A pliers assembly as in claim 1 in which the handle members and thejaw members are made as stainless steel precision castings.

7. A pliers assembly as in claim 1 in which the combined thicknesses ofthe two outer wall portions of the handle members and the two plateportions of the jaw members are not more than three-eighths of an inch.

8. A pliers assembly as in claim 1 in which the handle members are likemembers and the jaw members are spaced from each other by means ofbosses formed on 'the outer walls.

11. A pliers assembly as in claim I in which the outer wall portions ofthe handle members are precisely spaced from each other by means of aspacer carried on the pivot pin.

1. A pliers assembly in which the jaws are carried and are movable sothat the gripping faces on the jaws are substantially parallel throughtheir limits of movement, said pliers including: (a) a pair of handlemembers adapted for grasping by the user, each of said handle membershaving an outer wall portion; (b) a pivot pin adapted to retain thehandle members in a pivotal relationship to each other and disposed toretain said outer wall portions with a determined distance therebetween;(c) a pair of jaw members each having a gripping face portion, said jawmembers arranged so that the face portions are substantially paralleland disposed to be contiguous when brought together, each jaw memberhaving a rear plate portion and with each plate portion having aclearance means therethrough, said clearance means disposed toaccommodate the presence of the pivot pin when the plate portions of thejaw members are slidably retained between the outer wall portions of thehandle member; (d) a fixed short pin carried on the outer wall portionof each handle and a mating pin-receiving aperture formed in acontiguous portion of the rear plate portion of each jaw member anddisposed to receive and pivotally support said short pin, the pin andaperture being disposed a determined distance from the pivot pin; (e) afixed longer pin carried on the outer wall portion of each handle and amating pin receiving slot formed in a portion of the rear plate portionof each jaw member, the longer pins and slots being disposed adetermined distance from the pivot pin on the side opposite the shortpin, relief means formed in the rear plate portion of each jaw memberwhereby said longer pin of each handle may pass the rear plate portionof the jaw member contiguous therewith to respectively engage said slotin the rear plate portion of the other of said jaw members, and (f)means for mounting and retaining the short and longer pins in acantilever manner as the pliers are assembled and used.
 2. A pliersassembly as in claim 1 in which the short pin is carried forwardly ofthe pivot pin and the longer pin is carried rearwardly of the pivot pin.3. A pliers assembly as in claim 2 in which the outer wall portions ofthe handle meMbers and the plate portions of the jaw members are ofsubstantially the same thickness with each of the short pins being atleast slightly less in length than the thickness of a rear plate portionof a jaw member and with the longer pin of a length substantially longerthan the thickness of a rear plate portion of a jaw member and of alength of at least slightly less than the combined thicknesses of thetwo adjacent rear plate portions of the two jaw members.
 4. A pliersassembly as in claim 3 in which the axis of the short and long pin onone outer wall portion lays in a plane common with the axis of the pivotpin.
 5. A pliers assembly as in claim 4 in which the short and long pinsare disposed an equal distance from the pivot pin.
 6. A pliers assemblyas in claim 1 in which the handle members and the jaw members are madeas stainless steel precision castings.
 7. A pliers assembly as in claim1 in which the combined thicknesses of the two outer wall portions ofthe handle members and the two plate portions of the jaw members are notmore than three-eighths of an inch.
 8. A pliers assembly as in claim 1in which the handle members are like members and the jaw members arelike members with the handles and jaw members oriented at 180* to eachother.
 9. A pliers assembly as in claim 1 in which the clearance meansfor the pivot pin provided in the plate portion of the jaws areelongated holes formed in each jaw rear plate portion.
 10. A pliersassembly as in claim 1 in which the outer wall portions of the handlemembers are precisely spaced from each other by means of bosses formedon the outer walls.
 11. A pliers assembly as in claim 1 in which theouter wall portions of the handle members are precisely spaced from eachother by means of a spacer carried on the pivot pin.